--- /dev/null
+From a0761a301746ec2d92d7fcb82af69c0a6a4339aa Mon Sep 17 00:00:00 2001
+From: Johannes Berg <johannes.berg@intel.com>
+Date: Thu, 26 Mar 2020 15:09:42 +0200
+Subject: mac80211: drop data frames without key on encrypted links
+
+If we know that we have an encrypted link (based on having had
+a key configured for TX in the past) then drop all data frames
+in the key selection handler if there's no key anymore.
+
+This fixes an issue with mac80211 internal TXQs - there we can
+buffer frames for an encrypted link, but then if the key is no
+longer there when they're dequeued, the frames are sent without
+encryption. This happens if a station is disconnected while the
+frames are still on the TXQ.
+
+Detecting that a link should be encrypted based on a first key
+having been configured for TX is fine as there are no use cases
+for a connection going from with encryption to no encryption.
+With extended key IDs, however, there is a case of having a key
+configured for only decryption, so we can't just trigger this
+behaviour on a key being configured.
+
+Cc: stable@vger.kernel.org
+Reported-by: Jouni Malinen <j@w1.fi>
+Signed-off-by: Johannes Berg <johannes.berg@intel.com>
+Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
+---
+ net/mac80211/debugfs_sta.c | 3 ++-
+ net/mac80211/key.c | 20 ++++++++++++--------
+ net/mac80211/sta_info.h | 1 +
+ net/mac80211/tx.c | 12 +++++++++---
+ 4 files changed, 24 insertions(+), 12 deletions(-)
+
+--- a/net/mac80211/debugfs_sta.c
++++ b/net/mac80211/debugfs_sta.c
+@@ -5,7 +5,7 @@
+ * Copyright 2007 Johannes Berg <johannes@sipsolutions.net>
+ * Copyright 2013-2014 Intel Mobile Communications GmbH
+ * Copyright(c) 2016 Intel Deutschland GmbH
+- * Copyright (C) 2018 - 2019 Intel Corporation
++ * Copyright (C) 2018 - 2020 Intel Corporation
+ */
+
+ #include <linux/debugfs.h>
+@@ -78,6 +78,7 @@ static const char * const sta_flag_names
+ FLAG(MPSP_OWNER),
+ FLAG(MPSP_RECIPIENT),
+ FLAG(PS_DELIVER),
++ FLAG(USES_ENCRYPTION),
+ #undef FLAG
+ };
+
+--- a/net/mac80211/key.c
++++ b/net/mac80211/key.c
+@@ -6,7 +6,7 @@
+ * Copyright 2007-2008 Johannes Berg <johannes@sipsolutions.net>
+ * Copyright 2013-2014 Intel Mobile Communications GmbH
+ * Copyright 2015-2017 Intel Deutschland GmbH
+- * Copyright 2018-2019 Intel Corporation
++ * Copyright 2018-2020 Intel Corporation
+ */
+
+ #include <linux/if_ether.h>
+@@ -262,22 +262,29 @@ static void ieee80211_key_disable_hw_acc
+ sta ? sta->sta.addr : bcast_addr, ret);
+ }
+
+-int ieee80211_set_tx_key(struct ieee80211_key *key)
++static int _ieee80211_set_tx_key(struct ieee80211_key *key, bool force)
+ {
+ struct sta_info *sta = key->sta;
+ struct ieee80211_local *local = key->local;
+
+ assert_key_lock(local);
+
++ set_sta_flag(sta, WLAN_STA_USES_ENCRYPTION);
++
+ sta->ptk_idx = key->conf.keyidx;
+
+- if (!ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT))
++ if (force || !ieee80211_hw_check(&local->hw, AMPDU_KEYBORDER_SUPPORT))
+ clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
+ ieee80211_check_fast_xmit(sta);
+
+ return 0;
+ }
+
++int ieee80211_set_tx_key(struct ieee80211_key *key)
++{
++ return _ieee80211_set_tx_key(key, false);
++}
++
+ static void ieee80211_pairwise_rekey(struct ieee80211_key *old,
+ struct ieee80211_key *new)
+ {
+@@ -441,11 +448,8 @@ static int ieee80211_key_replace(struct
+ if (pairwise) {
+ rcu_assign_pointer(sta->ptk[idx], new);
+ if (new &&
+- !(new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX)) {
+- sta->ptk_idx = idx;
+- clear_sta_flag(sta, WLAN_STA_BLOCK_BA);
+- ieee80211_check_fast_xmit(sta);
+- }
++ !(new->conf.flags & IEEE80211_KEY_FLAG_NO_AUTO_TX))
++ _ieee80211_set_tx_key(new, true);
+ } else {
+ rcu_assign_pointer(sta->gtk[idx], new);
+ }
+--- a/net/mac80211/sta_info.h
++++ b/net/mac80211/sta_info.h
+@@ -98,6 +98,7 @@ enum ieee80211_sta_info_flags {
+ WLAN_STA_MPSP_OWNER,
+ WLAN_STA_MPSP_RECIPIENT,
+ WLAN_STA_PS_DELIVER,
++ WLAN_STA_USES_ENCRYPTION,
+
+ NUM_WLAN_STA_FLAGS,
+ };
+--- a/net/mac80211/tx.c
++++ b/net/mac80211/tx.c
+@@ -590,10 +590,13 @@ ieee80211_tx_h_select_key(struct ieee802
+ struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)tx->skb->data;
+
+- if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT))
++ if (unlikely(info->flags & IEEE80211_TX_INTFL_DONT_ENCRYPT)) {
+ tx->key = NULL;
+- else if (tx->sta &&
+- (key = rcu_dereference(tx->sta->ptk[tx->sta->ptk_idx])))
++ return TX_CONTINUE;
++ }
++
++ if (tx->sta &&
++ (key = rcu_dereference(tx->sta->ptk[tx->sta->ptk_idx])))
+ tx->key = key;
+ else if (ieee80211_is_group_privacy_action(tx->skb) &&
+ (key = rcu_dereference(tx->sdata->default_multicast_key)))
+@@ -654,6 +657,9 @@ ieee80211_tx_h_select_key(struct ieee802
+ if (!skip_hw && tx->key &&
+ tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
+ info->control.hw_key = &tx->key->conf;
++ } else if (!ieee80211_is_mgmt(hdr->frame_control) && tx->sta &&
++ test_sta_flag(tx->sta, WLAN_STA_USES_ENCRYPTION)) {
++ return TX_DROP;
+ }
+
+ return TX_CONTINUE;
projects / openwrt / openwrt.git / commitdiff